Automatic air-brake-pressure adjuster.



110.8%,917. PATENTEDV'APR. 7, 1908.

V .U. s. SMITH.

AUTOMATIC AIR BRAKE PRESSURE ADJUSTER. APPLICATION FILED FEB. 12. 1907.

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ULYSSES S. SMITH, OF SACRAMENTO, CALIFORNIA.

AUTOMATIC AIR-BRAKE-PRESSURE ADJUSTER.

Specification of Letters Patent.

Application filed February 12, 1907.

Patented April 7, 1908.

Serial No. 357,101.

To all whom it may concern:

Be it known that I, ULYSSES S. SMITH, a citizen of the United States,residing at Sacramento, in the county of Sacramento and State ofCalifornia, have invented certain new and useful Improvements inAutomatic Air-Brake-Pressure Adjusters; and I do declare the followingto be a full, clear, and exact description of the same, such as willenable others skilled in the art to which it apertains to make and usethe same, reference lieing had to the accompanying drawings, and thecharacters of reference marked thereon, which form a part of thisspecification.

This invention relates to improvements in means of adjustingautomatically the pressure on' air-brakes used in connection withrailway rolling stock, and particularly on freight cars, my object beingto produce a means whereby the braking pressure on all cars may be madeuniform according to their weight whether empty or loaded. This object Iaccomplish by means of an auxiliary cylinder connected to the brakecylinder of the air-brake, a tension spring regulated piston arranged insaid cylinder, and a means for regulating the tension of said spring bythe weight of the car; also by such other and further construction aswill appear by a perusal of the following specification and claims.

In the drawings similar characters of reference indicate correspondingparts in the several views.

Figure 1 is a side elevation of about one half a freight car, showing myimproved device arranged thereon. Fig. 2 is a side elevation enlarged ofthe device partly in section. Fig. 3 is side elevation of a tensionspring regulator employed in connection with the improved device.

' 1 designates a car having the usual airbrake attachment. 9

2 is the reservoir of the air-brake and 3 is the brake cylinder.

Connected to the brake cylinder 3 by means of a passage 4' is anauxiliary cylinder 4 in which is an elongated slot or port 5 extendingtransversely thereof as shown.

Threaded into the rear end of the cylinder 4 is a plug 6 having ashoulder 7 on its inner end and a square shoulder 8 on its outer end,said plug and its parts having an interior orifice 9. And in thisorifice 9 is a rod 10 provided within the cylinder with a shoulder 11hearing against the sides of said cylinder and against the shoulder 7.The inner end of said rod 10 is provided with a sleeve 12 in which isslidably arranged a rod 13 of a piston 14 operating in said cylinder infront of said slot 5. Bearing between the said piston 14 and shoulder 11is a tension spring 15 for the purpose as will appear.

In the outer end of the rod 10 is a slot 10, and 16 is a lever pivotedto the under side of the car and extending through said slot 10". Aspring 17 is connected to the lower end of said lever and to the underside of the car, and operating to maintain the lever yieldably inwithdrawn position, as hereby explained.

Pivotally mounted on the bottom of the car over one of the axles 18 ofthe wheels of the said car, is a depending arm 19 having a slot 20 atits lower end. Pivoted on said arm 19 is a lever 21 connected at one endby a rod or cable 22 to the free end of the lever 16 and connected atthe other end by a link 23 to a wheel 24 slidably journaled in the slot20. Formed as a component part of said lever 21 is a curved ratchet rack21 with which a pawl 25 pivotally secured to the arm 19, engages. spring26 holds said pawl 25 in engag'" or? with said ratchet. A wire cable 27a. connected with the said pawl 25 and extends thence over a pulley 28to the top of a lever 29, the lower end of said lever extending into thepath of the outer terminal of the piston rod 30 of the brake cylinder.

In using the device the plug 6 is adjusted by means of the squaredportion 8 until the shoulder 7 pressing against the shoulder 11 causesthe spring 15 to be of such tension that it will permit all air from thebrake cylinder 3, save and except enough to brake the empty car, sayfifty pounds, to pass through the port 4, and thence displace the piston14 and then pass to the atmosphere through the port 5. Thus when theempty car is braked there is no surplus or heavy pressure on the emptycar. As the car is loaded the weight causes the bed of the car to lower,thus causing the arm 19 to move downward until the wheel 24 engages withthe axle 18, and as the car is loaded still more the wheel 24 movesupward in the slot 20, thus causing the link 23 to drive the outer endof the lever 21 upward and the inner end downward, as shown in dottedlines Fig. 2. This action causes the rod or cable 22 to pull the lever 16 inward, which action causes the rod 10 to be forced inward, thusincreasing the tension of the spring 15 and thereby causing more of theair brake is applied. hen this occurs, the piston head 30 of the brakemoves outwardly and engages the lever 29 and moves it outwardly. Thisaction causes the upper part of said lever to pull on the cable 27 thusreleasing the pawl 25 from the ratchet rack 21 and permitting wheel 24to drop if the car has been emptied, and also permitting the spring 15to resume its normal position, but if the car remains loaded, then. theweight holds said spring and its parts in their locked positions. Thusit will be seen that I have produced a means whereby, when a carisempty, only sufficient air pressure is retained to brake said car, thuspreventing the same from sliding and grinding unnecessarily, which wearsflat places 011 the wheels of the cars and renders them useless. Also ameans whereby the braking pressure is gradually increased as the load onthe car increases, thus graduating the braking power of he car accordingto the weight thereof.

Fig. 3 shows a modified means for regulating the tension of the spring15. In this construction the rod or cable 22 is connected to an L-shapedlever 31 pivotally mounted to an arm 32 pivotally secured in turn to thelower and fixed bolster 33 of the truck of the car, one arm of saidL-shaped lever engaging with the under side of the movable bolster 34 ofsaid truck, said lever having a ratchet rack 35 similar to the rack 21*.On an arm. 36 forming a part of the arm 32 is pivotally mounted a bellcrank 37, one arm thereof engaging with the top of the bolster 34 andthe other arm 37' acting as a pawl and engaging with the rack 35. Inpractice as the car is loaded the bolster 34 moves gradually downwardthus causing the lever 31 to. pull on the rod 22 and thereby increasingthe tension of the spring 15 in the same manner as described in theother arrangement. The pawl finger 37 engaging with the ratchet rack 35holds said spring in such position until the load is removed from thecar, when the upward rise of the bolster 34 releases it, thus relievingthe said tension.

From the foregoing description it will be seen that I have, by myinvention, substantially fulfilled the objects set forth in the preambleof this specification.

It is well known that in a train of cars there are always a few emptiesintermingled with the loaded cars. Now when it becomes necessary toincrease the braking power of a train under the present arrangement, thesame braking power is applied to all the cars indiscriminately. This ofcourse causes the wheels of the empties to slide and. wear for a certaindistance before the speed is checked or the train stopped. The improveddevice, however, as described, obviates all the unnecessary braking ofempty cars and graduates the braking power according to the weight ofthe cars. A higher train line pressure is also gained, which admitsquicker action on the brakes, both in setting and re leasing, and powerto handle the cars whether empty or loaded, or both, is increased and inemergency cases, greater speed can be made as the power can be carriedto brake the ears and keep them more effectually under control.

Having thus described my invention, what I claim as new and useful anddesire to secure by Letters Patent is:

1. The combination with the body of a car having an air brake cylinderdepending there from, of an auxiliary cylinder, connecting means betweenthe brake cylinder and the auxiliary cylinder, means for permitting thepassage of air from said auxiliary cylinder. means operating in saidauxiliary cylinder for controlling and regulating said. passage of air,and means operated by the movement of the body of the car forautomatically actuating said controlling and regulating means.

. 2. In a device of the kind described a cylinder connected with brakecylinder of an air brake, an elongated port in said cylinder, a pistonarranged in said cylinder, adapted to open or close said port, a tensionspring arranged between the rear of the piston and the rear of thecylinder, and means for automat ically regulating the tension of saidspring, as set forth.

3. In a device of the kind described a cylinder connected to brakecylinder of an air brake, an elongated port arranged in said cylinder, apiston arranged in said cylinder and adapted to open and close saidport, a spring regulating the position of the said piston by the weightof the vehicle to which the brake is attached, as specified.

4. In. a device of the kind described, a vehicle, a cylinder connectedto brake cylinder of the air brake thereof, an elongated port in saidcylinder, a piston arranged in said cylinder, an adjustable plug in therear of said cylinder, a rod extending through said plug and having ashoulder on its inner end, a spring bearing between said piston and saidshoulder, a slot in the outer end of said. rod, a lever pivoted to theunderside of the said vehicle and extending through said slot, and meansfor operating said lever by the weight of the vehicle as set forth.

5. In a device of the character described a depending arm pivotallymounted on the underside of a vehicle just above one axle thereof, a'slot in the lower end of said arm, a wheel slidably j ournaled throughsaid slot, an

upward link secured to said Wheel, a lever pivoted to said arm andsecured at one end to said link, a lever pivoted to the under side of acar, a rod or cable connecting said levers, and means in connection Withsaid last named lever for regulating-the amount 0i air passing from thebrake cylinder of an air brake, as described.

6. In a device of the character described, a vehicle, a means forpermitting the exhaust of air from brake cylinder of an air brake,

means for regulating said exhaust by the weight of the vehicle, andmeans for regulating said position of said last named means with thepiston rod of the braking cylinder, as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

ULYSSES S. SMITH. Witnesses:

PERoY S. WEBSTER, FRANK H. CARTER.

